In my mid 20s my GF said she'd be into MFM if I wanted to. Sometime later, with two friends, we had MFMM - her first group sex experience. I had to put my emotions to the back of my mind and focus on how hot she looked between us.
In my 30s I went to a swingers club, single. I was invited back for a greedy girls event and with six other men a woman asked to join her, we spent a couple of hours passing her around, gradually being harder and rougher as we saw she was enjoying it. Her husband checked in a few times, but didn't stay to watch. I felt sort of out of body, watching myself doing things I'd seen in porn. She was totally in charge and really enjoying us.
A couple I met online for MFM and my first (all our first) DVP invited me to a holiday cottage, with the husband and five other men. Three of us in our 40s (for our experience, she said) and three in their early 20s (for young energy). She had a huge appetite and kept us all busy for the evening, much of the night and into the next day. I've never seen such energy, hunger and abandon. I don't know how she did it. We all really went to town, double penetrating her, pounding her hard in quick succession, keeping her mouth full. It was rude, sweat and cum soaked, full on animalistic and very memorable.
Finally, with a girlfriend who had a few gangbangs in the past and really liked the idea of another. We tested the water with MFM with a friend. Then spent a couple of months vetting some well verified, experienced, communicative men. Booked a nice hotel room. Five guys in mid 30s - 40s arrived, waited in the bar until we called them up. She hadn't met any of them as I'd been the "gatekeeper". After an hour of chatting, flirting, getting comfortable, she let me know she wanted to go ahead. She wanted to be quite passive and just let us all "do what we wanted with her". She liked being put in different positions, thrown around a bit, picked up and passed around, "used" fairly forcefully. Just able to let go, knowing I was looking after her. It wasn't emotionally easy seeing her like that, but I'd anticipated it and tried to mentally prepare myself. I tried to switch off my thoughts and just see her in purely sexual terms, kind of reducing her to just a woman who loved being fucked. A lot. I took part some of the time, or suggested she do things I wanted to see. The guys all used condoms, but came all over her body, face, in her mouth, at least once. She could orgasm very easily from penetration and after a couple of hours, was a total puddle of exhausted pleasure. The guys dressed, left and before she showered we had "reconnection sex" which I'll never forget. The sight of her, smeared in cum, hair stuck to her, eyes unfocussed, laughing about what a "whore" she was.
Unfortunately, a few weeks later she started having regrets and doubts. She shouted at me that "if I really loved her I never would have allowed it." Bit of insecurity and shame, no gratitude for the challenge it was for my emotions